A method for the production of a wrapped yarn is known (West German O/S 1 685 881=British Pat. No. 1,159,510=U.S. Pat. No. 3,478,506). By the false-twisting which is imparted to the bundle of textile fibers emerging from a pair of delivery rollers on its way to the hollow shaft of a wrapper member having a hollow spindle, the bundle of textile fibers obtains a sufficiently great strength before wrapping so that breakages are avoided. The hollow spindle can therefore have a greater distance from the delivery rollers as compared to other known methods and devices in which the bundle of textile fibers remains without twist and the inlet opening to the hollow spindle is arranged at a distance corresponding with the average length of the staple fibers (U.S. Pat. Nos. 3,328,946 and 3,831,369). This facilitates attendance and avoids adaptation of the distance to the length of fiber at the time.
The productive capacity in the production of such a wrapped yarn is restricted by the speed of rotation of the hollow spindle to which the speed of delivery from the delivery rollers and the draw-off speed of the draw-off rollers must be adapted if a predetermined number of wraps per unit length are to be applied to the bundle of textile fibers.
It has been previously proposed to wrap an internal thread with two covering threads which run off two bobbins arranged one behind the other on a hollow spindle and rotate with it (West German Pat. No. 2,359,435). It is thereby possible to double the production. However, the outlay in material necessary to do this and the power requirement for the operation of the device are considerable.
The object of the present invention is to create a method and a device which avoids the aforesaid disadvantages and enables the simplified production of a wrapped yarn at a higher speed of production.